The invention relates to testing mobile communications systems.
In a mobile communications system, such as cellular or personal communications services (PCS) systems, mobile telephones communicate through nearby radio base stations and a mobile switching center. The switching center can connect a mobile telephone to another wireless telephone or to a wired telephone through a public switched telephone network (PSTN).
A cellular or PCS system is made up of a number of cells each with a base station having transmitting and receiving antennas. Mobile telephones in the cells can request access by transmitting predetermined messages through control channels to the mobile switching center. Access to the system can then be provided to the mobile telephone on an available voice channel. In addition, as a mobile telephone moves from one cell to another, the mobile switching center handles hand-off of the mobile telephone from one cell to another.
The mobile switching center may be run under control of switching software to handle accesses by mobile telephones, store locations of mobile telephones as they move between cells, and handle hand-offs of mobile telephones between cells. During development of components (both hardware and software) of mobile switching centers in a mobile communications system, various types of tests may be performed to determine whether the components are operating properly. Such tests may be performed using software simulation of certain parts of a mobile communications system, which may include software emulation of mobile units and base stations. To test actual operation of a system, one or more mobile telephones may be physically moved within a cell and between cells to test access and hand-off capabilities of the mobile switching center.
With conventional test techniques, however, the number of real mobile telephones and movement patterns may be limited since one or more mobile telephones have to be physically moved around in a cell and between cells. The personnel and equipment needed to physically move the mobile telephones may be costly. In addition, it may be time consuming to move real mobile telephones around in a geographic area covered by a mobile communications system, which may further increase costs associated with testing.
Thus, a need exists for an improved method and apparatus for testing a mobile communications system.